Apex police said 17-year-old Timothy Castaneda was partying with friends behind the Beaver Creek Cinema on Oct. 6 when he collapsed.
Police said there were about 20 teenagers at the party and they all fled when officers arrived about 2 a.m.
Three teenagers, however, stayed with Castaneda, who was rushed to the hospital. Castaneda died over the weekend.
Grief counselors were at Apex High school Monday.